It's because it's a lie. Many times the copied sites have copy asserting that so-and-so is a great firm, make great products, when they haven't made anything. I

It's because it's a lie. Many times the copied sites have copy asserting that so-and-so is a great firm, make great products, when they haven't made anything. If isn't such a big deal, why don't the copied sites say 'We copied this entire website, minus copy changes, from X.'?